It is known that in some print heads, and in particular inkjet print heads, nozzle layers are provided with LSE (low surface energy) layers on the nozzle surfaces. Such LSE coatings provide for a high contact angle of ink on the nozzle layer surface. Consequently, the LSE coatings reduce the size of puddles and minimize ink mixing on the nozzle surface between the nozzles, which may for example occur because of ink sputtering near one or multiple nozzles or because of other reasons. It appears that during manufacturing of the nozzles, chambers and/or slots of the print head, certain post processing methods such as ashing or etching can negatively decrease the contact angle of the LSE coating.